Re: updated join removal patch - Mailing list pgsql-hackers

From Tom Lane
Subject Re: updated join removal patch
Date
Msg-id 4752.1253300771@sss.pgh.pa.us
Whole thread Raw
In response to Re: updated join removal patch  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: updated join removal patch
List pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> On Fri, Sep 18, 2009 at 1:58 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Robert Haas <robertmhaas@gmail.com> writes:
>>> Mmm, I like that. �Putting that bunch of hairy logic in a subroutine
>>> instead of repeating it in several places definitely seems better. �I
>>> don't really like the name "clause_matches_join", though.

>> It was the first thing that came to mind ... got a better idea?

> clause_has_well_defined_sides()?

Nah ... they're "well defined" in any case, they might just not be what
we need for the current join.  As an example,
(a.f1 + b.f2) = c.f3

would be usable if joining {A B} to {C}, but not when joining
{A} to {B C}.
        regards, tom lane


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